The club captain has recovered
from the knock he picked up in Monday's League One success at Arbroath
but Kyle Hutton is out with a broken leg incurred on U20s duty.
Striker Dean Shiels could come into contention for Saturday's game
and make his first appearance since August following a knee injury.
McCoist is expecting another tough test at a ground where Rangers have had their problems in recent seasons.
"I'm already reading comments after Falkirk's good victory at the
weekend - quite rightly - from one or two of their lads," he said.
"They knocked us out of the League Cup a couple of seasons ago and are doing well in the league just now.
"They are looking forward to the Rangers game and they're looking to
put one over on us again. You'd absolutely expect them to say that.
"If there was ever any doubt about how up for the game Falkirk are,
you just have to look at their quotes in the newspapers. They're full of
confidence.
"We've had them watched and they beat Livingston 4-1 recently, so it's a tough game for us."
Falkirk manager Gary Holt can call on loan signing Mark Millar after Dundee United agreed to their request.

Falkirk technical director Alex Smith
: "It is a strange cup tie as we are playing a strong Rangers side
and some people see us as favourites as we are in the league above them.
"It will be a great test for our young players and one they can rise to."
Rangers manager Ally McCoist:
"I'm already reading comments after Falkirk's good victory at the weekend - quite rightly - from one or two of their lads.
"They knocked us out of the League Cup a couple of seasons ago and are doing well in the league just now.
"They are looking forward to the Rangers game and
they're looking to put one over on us again. You'd absolutely expect
them to say that.
"If there was ever any doubt about how up for the game
Falkirk are, you just have to look at their quotes in the newspapers.
They're full of confidence.
"We've had them watched and they beat Livingston 4-1 recently, so it's a tough game for us."